Our goal is to enhance strengths previously identified and eliminate weaknesses. The focus remains development of a transplacental chemoprevention model integrated with projects 1 & 3 to address mechanisms. We examine blocking mechanisms and risk VS benefit to mother and fetus with a focus on epigenetics demanding tight integration among projects. The scope is only possible with the participation of the other projects and cores. The central hypothesis is sulforaphane (SFN) and indole-3-carbinol (I3C) are chemopreventive agents, as are the whole foods, in a PAH-transplacental lymphoma, lung, liver and ovary cancer model. Mechanisms are blocking and/or epigenetic, the degree depending on the phytochemical. Focus on the same phytochemicals enhance integration and synergism. We test the hypotheses by pursuit of 3 integrated aims progressing from discovery and mechanistic studies in pregnant mice to a small human trial. The translational nature is also enhanced by use of a humanized mouse. The trial with human volunteers takes advantage of the remarkable sensitivity of accelerator mass spectromety (AMS). Specific Aim 1: Test the response of humanized mice; examine 130 dose-response and compare purified phytochemicals (at human dietary levels) to whole foods; test windows of maternal dietary I3C and SFN exposure; test post-initiation suppression; utilize lung- and liver-specific models; determine role of nrf2 signaling in a gene dosage study; and test transplacental cancer chemoprevention in an F2 generation. Specific aim 2: Focus entirely on epigenetics with a known target (CYP1B1), followed by p21, gstp1 and cyclind2, promising targets in common with projects 1 & 3. Specific aim 3: Utilize AMS to determine pharmacokinetics of a non-carcinogenic PAH in humans and impact of I3C pretreat. Assess bioavailability of I3C derivatives and compare I3C with the whole food (Brussels sprouts). This is a highly translational aim that serves as a prelude to further studies of PAH exposure and transplacental chemoprevention. This project is highly integrated with the other 2 as we will provide tissues to both and, in return, will be able to determine the similarities and differences of chemoprevention mechanisms between mouse and human.